1. Field of the Invention
The present invention relates to hand splints. More particularly, the present invention relates to a hand splint which reduces deviation of the finger(s) in an ulnarward direction and brings the fingers into neutral alignment along a mid-longitudinal axis of the hand and forearm. Even more particularly, the present invention relates to a hand splint for supporting the metacarpophalangeal (MP) joints and for realigning the proximal phalanges when indicated by uncontrolled ulnar drift.
2.Description of Prior Art
The present invention is intended to be used by persons who experience uncontrolled deviation of the fingers in an ulnarward direction secondary to joint disruption caused by disease, such as Rheumatoid arthritis, or trauma affecting the hand. Persons with uncontrolled ulnar deviation experience diminished or lost hand function due to the inability to stabilize the fingers at the MP joints which is necessary to form and maintain a fisted posture or to achieve pinch between the thumb and finger(s).
Use of the impaired hand without any external support will cause progression of the instability at the MP joints as proportionally more pressure must be exerted to sustain objects in the hand or fingers. The required pressure furthers the stretching and destruction of the soft tissues at the joints and eventually renders them incapable of maintaining stability around the joint.
The loss of functional use of the hand for all but simple non-resistive tasks leads to a loss of independence for the affected person. Persons experiencing severe forms of arthritis frequently require assistance with daily tasks such as dressing, feeding and hygiene activities. Such persons may also be incapable of performing vocational activities due to the loss of hand function.
To alleviate this disruptive condition, there has been proposed, heretofore, splints and similar devices to assist such persons and to impact some function to the hand of the user. Such devices of this nature have been available for over ten years. All such prior art splint devices generally fall into two basic categories. The first category involves those splint devices which are comprised of flexible woven materials sewn into patterns that seek to support the fingers and hand, or more commonly, the fingers, hand and wrist. The flexible material splints frequently include flexible or rigid stays positioned to limit joint motion so as to offer support through immobilization of the joints. These splints are held in place on the hand or arm by the use of straps that incorporate a hooked area and an interlocking brushed material. The straps are positioned on the device to allow for independent donning and doffing of the device. Persons with arthritis frequently do not have sufficient strength to pull open these straps or to apply sufficient force on the strap for secure closure of the device on the hand and arm and therefore require the assistance of a care giver to don and doff the device. If this category of device is not positioned securely on the hand with firmly applied strapping, it may be displaced during activities rendering it an impediment to function rather than an assist.
The second category includes splint devices made from metal, plastic or wire formed to cover the palmar surface of the hand and include some form of semi-rigid or flexible pieces formed to position the fingers out of deviation. These splints have the advantage of being lightweight and of providing adjustability through the use of malleable fingers extensions or through the use of elastic components.
However, the second category of splint devices, as well as the first, suffer a disadvantage in that they cover the palmar surface of the hand with a bulky foam and metal frame rendering it more difficult to carry or manipulate objects. These devices also limit the ability of the wearer to close their hand into a fist because the devices do not allow motion in a plane of flexion towards the palm and extension away from the palm at the MP joints.
A further disadvantage of the prior art devices is that they are static in design. Designs which are static in nature allow no motion at the MP joints and, therefore, limit hand function as the hand must perform tasks without active flexion or extension.
In addition, the prior art devices as described are made from either flexible woven materials or from lightweight wire covered by a water resistant cushioning. These materials, while soft and providing cushioning around the involved fingers and hand, do not withstand repeated or aggressive activities and, therefore, require regular replacement which is costly and inconvenient.
It is therefore the goal of the present invention to overcome the problems heretofore encountered in the prior art. It is a purpose of the present invention to provide a hand splint which by placing the body of the splint on the dorsum of the hand leaves the palmar surface of the hand free of any encumbrance and allows for unimpeded functional grasp and release.
Furthermore, it is a purpose of the present invention to provide a hand splint which is hinged to allow for improved hand function in active flexion and extension.
In addition, the present invention allows for positioning and correction of each finger individually by the use of a finger alignment component that can be readily contoured to meet the shape and position of each finger. The present invention allows for free motion in a plane of flexion towards the palm and extension away from the palm at all joints of the hand.
It is a further purpose of the present invention to provide a hand splint that successfully maintains the fingers of the hand in a neutral alignment as measured from a longitudinal line bisecting the forearm and the hand and that also allows for fill functional use of the hand.
It is a still further purpose of the present invention to provide a hand splint made from materials which withstand repeated or aggressive activities so as to improve convenience and cost-effectiveness.
The present invention is designed to restore stability to the joints of the hand and thereby restore hand function and greater independence in all tasks.